JP7380086B2 - Image forming device - Google Patents

Description

The present invention relates to an image forming apparatus including a developing device, and particularly to cooling control of the developing device.

In the developing device of the image forming apparatus, the developer is conveyed while being stirred, and the developer is applied to the electrostatic latent image on the image carrier through a developing roller to make the electrostatic latent image on the image carrier visible. It is developed into an image (developer image). For example, in an image forming apparatus, when the temperature of the developing device that carries and transports developer increases due to continuous printing, etc., the printing operation is restricted or interrupted to prevent thermal deterioration of the developer. Cooling takes place.

For example, in the image forming apparatus described in Patent Document 1, the temperature inside or around the developing device is detected, and when the detected temperature exceeds a threshold temperature, the number of pages that can be continuously formed is limited to a predetermined number or less. The intermittent printing operation mode is set, and then, when the detected temperature in the intermittent printing operation mode becomes less than a release temperature that is lower than the above-mentioned threshold temperature, the restriction on the number of pages on which continuous image formation can be performed is canceled.

Patent No. 5863011

However, in Patent Document 1, the number of pages that can be continuously printed is not completely proportional to the amount of heat that causes the temperature of the developer to rise, and even when the number of pages that can be continuously printed is limited, the number of pages that can be continuously printed is The temperature may exceed the threshold temperature and thermal deterioration of the developer may not be prevented. Furthermore, if there is a discrepancy between the detected temperature of the developing device and the temperature of the part of the developer that is exposed to the highest temperature, the temperature of the developer may exceed the upper limit temperature of the developer, causing thermal deterioration of the developer. increases. However, if the threshold temperature is lowered, thermal deterioration of the developer will be reduced, but printing will be restricted or interrupted more than necessary, and convenience will be significantly hindered, so lowering the threshold temperature is not recommended. is not desirable.

Furthermore, due to the effects of global warming in recent years, examples of use in high-temperature environments are increasing, and the melt viscosity of developers is becoming lower in order to comply with environmental regulations. For this reason, it is expected that there will be an increase in cases where printing is restricted or interrupted and convenience is hampered. For example, if a user makes a printing request without knowing that printing is restricted, the user may have to wait a long time until printing is finished, which significantly reduces convenience.

The present invention has been made in view of the above circumstances, and an object of the present invention is to improve convenience by appropriately reducing thermal deterioration of a developer while avoiding a decrease in printing productivity as much as possible.

An image forming apparatus according to one aspect of the present invention is an image forming apparatus including a developing device, wherein the developing device applies a developer to an electrostatic latent image formed on an image bearing member to generate the electrostatic latent image. a developer storage unit having a developing roller that develops a latent image into a visible image, and a stirring member that agitates the developer while conveying the developer along the developing roller, and supplies the developer to the developing roller; an in-machine temperature detection section that is disposed on an outer wall surface of the developer accommodating section around a drive input section that drives the developing roller and the stirring member, and that detects the temperature of the outer wall surface of the developer accommodating section as an in-machine temperature; , the image forming apparatus includes a display section, an operation section operated by a user, an external temperature detection section that detects the temperature outside the image forming apparatus, and when receiving a print request, ( i) When the internal temperature detected by the internal temperature detection unit is lower than a predetermined first threshold temperature, a first cooling mode is set in which continuous printing is possible, and cooling control is performed in the first cooling mode. (ii) when the machine interior temperature detected by the machine interior temperature detection unit is equal to or higher than the first threshold temperature, the machine interior temperature detected by the machine interior temperature detection unit; and a second cooling mode in which intermittent printing is performed at a development drive duty ratio determined by the external temperature detected by the external temperature detection section, and the printing related to the print request is executed in the intermittent printing. is displayed on the display unit in advance, and upon receiving a print start instruction via the operation unit, performs cooling control in the second cooling mode and starts printing related to the print request in the intermittent printing, The apparatus further includes a control section that cancels printing related to the print request upon receiving a cancellation instruction via the operation section.

According to the present invention, it is possible to improve convenience by appropriately reducing thermal deterioration of the developer while avoiding a decrease in printing productivity as much as possible.

1 is a sectional view showing an image forming apparatus according to a first embodiment of the present invention. FIG. 3 is a longitudinal cross-sectional view showing a set of photoreceptor drums, a developing device, etc. in each image forming unit. FIG. 3 is a cross-sectional view showing a developer storage section of the developing device. 1 is a functional block diagram showing the main internal configuration of an image forming apparatus according to a first embodiment; FIG. FIG. 5 is a functional block diagram showing the main internal configuration of the drive section shown in FIG. 4. FIG. FIG. 3 is a diagram showing a reference table for specifying a developing drive duty ratio. FIG. 3 is a diagram for explaining a developing drive duty ratio expressed as a ratio between printable time and print standby time. (A) Diagram showing an example of printing time when a print request with a print request of 72 sheets is received in the second cooling mode, (B) A print request with a print request of 36 sheets is received in the second cooling mode FIG. 7 is a flowchart showing cooling control of the developing device in the image forming apparatus of the first embodiment. It is a figure showing an example of a display screen of a display part. FIG. 3 is a functional block diagram showing the main internal configuration of an image forming apparatus according to a second embodiment. 7 is a flowchart showing cooling control of a developing device in an image forming apparatus according to a second embodiment. FIG. 7 is a diagram for explaining a developing drive duty ratio of a first modification. FIG. 7 is a diagram showing a determination table in which the intermittent printing upper limit number of sheets is set in advance for each correspondence relationship between the input data of the internal temperature and the external temperature. 7 is a flowchart illustrating cooling control of a developing device in an image forming apparatus according to a second modification. (A) and (B) are diagrams each for explaining intermittent printing in a second modification.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing an image forming apparatus according to a first embodiment of the present invention. The image forming apparatus 10 includes an image reading section 11 and an image forming section 12.

The image reading unit 11 has an image sensor that optically reads the image on the document paper, and the analog output of this image sensor is converted into a digital signal to generate image data representing the image on the document paper.

The image forming unit 12 prints an image indicated by the image data on recording paper, and includes an image forming unit 3M for magenta, an image forming unit 3C for cyan, an image forming unit 3Y for yellow, and an image forming unit 3Y for black. The image forming unit 3Bk is provided. In each of the image forming units 3M, 3C, 3Y, and 3Bk, the surface of the photoreceptor drum 4 is uniformly charged, the surface of the photoreceptor drum 4 is exposed, and an electrostatic latent image is formed on the surface of the photoreceptor drum 4. , the electrostatic latent image on the surface of the photoreceptor drum 4 is developed into a visible image (developer image), and the visible image on the surface of the photoreceptor drum 4 is transferred to the intermediate transfer belt 5 . As a result, a colored visible image is formed on the intermediate transfer belt 5. This color visible image is secondarily transferred onto the recording paper P conveyed from the paper feed section 14 through the conveyance path 8 in the nip area N between the intermediate transfer belt 5 and the secondary transfer roller 7 . Note that the photosensitive drum 4 is an example of an image carrier in the claims.

Thereafter, the recording paper P is heated and pressurized by the fixing device 15, the visible image on the recording paper P is fixed by thermocompression bonding, and the recording paper P is further discharged to the discharge tray 17 through the discharge roller 16.

FIG. 2 is a longitudinal sectional view showing a set of photosensitive drums 4, developing devices 22, etc. in each of the image forming units 3M, 3C, 3Y, and 3Bk. Further, FIG. 3 is a cross-sectional view showing the developer storage section 31 of the developing device 22. As shown in FIG.

As shown in FIG. 2, each of the image forming units 3M, 3C, 3Y, and 3Bk is provided with a photosensitive drum 4, a developing device 22, a primary transfer roller 6, and the like. Around the photoconductor drum 4, there is a static eliminator 24 that eliminates static electricity from the surface of the photoconductor drum 4, a cleaning section 25 that cleans toner remaining on the surface of the photoconductor drum 4, and a cleaning section 25 that uniformly charges the surface of the photoconductor drum 4. A charging section 26, an exposing section 23 for forming an electrostatic latent image on the surface of the photoreceptor drum 4, and the like are provided. The developing device 22 is provided with a developing roller 27, a layer regulating member 28, a developer accommodating section 31 containing developer, two spiral feeders 32 that circulate and transport the developer, and the like. Note that the spiral feeder 32 is an example of a stirring member in the claims.

In this embodiment, a one-component magnetic toner is used as the developer contained in the developer storage section 31 of the developing device 22. The developing roller 27 includes a sleeve made of metal such as aluminum, and a magnet having a developing pole, a layer regulating pole, etc. provided inside the sleeve. Furthermore, the surface of the sleeve of the developing roller 27 is formed with unevenness having a predetermined roughness in order to stabilize the conveyance of the developer.

The layer regulating member 28 regulates the layer thickness of the developer on the surface of the developing roller 27 . Specifically, the layer regulating member 28 is composed of a magnetic blade and a magnet, and generates a magnetic field between the layer regulating pole of the magnet in the developing roller 27 and the developing roller 27 due to the gap with the sleeve of the developing roller 27. A thin layer of developer is formed on the surface of 27.

As shown in FIGS. 2 and 3, the developer storage section 31 has two supply conveyance paths 31A and a reflux conveyance path 31B, which are arranged in parallel to the developing roller 27 and partitioned by a partition wall 29. The supply conveyance path 31A and the reflux conveyance path 31B are connected through connecting paths 31C and 31D at both ends of each to form a circulation conveyance path in which the developer circulates. A spiral feeder 32 is provided in each of the supply conveyance path 31A and the reflux conveyance path 31B. Each spiral feeder 32 is rotationally driven in the direction of the arrow by a drive section 47 shown in FIG. 4, which will be described later.

In the supply conveyance path 31A, the developer is transported by the spiral feeder 32 of the supply conveyance path 31A from the upstream side in the developer conveyance direction to the downstream side in the conveyance direction (from one end side of the developing roller 27 to the other end side) in the direction of the arrow. The toner is stirred while being conveyed to the developer roller 27, and then sent out to the reflux conveyance path 31B through one connecting path 31C. In addition, in the reflux conveyance path 31B, the developer is stirred while being conveyed by the spiral feeder 32 of the reflux conveyance path 31B in a direction opposite to the conveyance direction in the supply conveyance path 31A, and then passes through the other connecting path 31D to the supply conveyance path. Returned to 31A. Thereby, the developer is supplied to the developing roller 27 while being circulated and conveyed.

The developer storage section 31 is provided with a developer replenishment port (not shown), and the amount of developer stored in the developer storage section 31 is maintained by replenishing the developer through this replenishment port. be done.

The developing roller 27 and the photosensitive drum 4 are rotationally driven in the direction of the arrow by a drive section 47 shown in FIG. 4, which will be described later. A developer is supplied to the sleeve surface of the developing roller 27 , a thin layer of developer is formed on the sleeve surface of the developing roller 27 by the layer regulating member 28 , and the developer on the sleeve surface of the developing roller 27 is applied to the photoreceptor drum 4 . A visible image (developer image) is formed on the surface of the photoreceptor drum 4 by being added to the electrostatic latent image formed on the surface.

Next, a configuration related to control of the image forming apparatus 10 will be described. FIG. 4 is a functional block diagram showing the main internal configuration of the image forming apparatus according to the first embodiment. As shown in FIG. 4, the image forming apparatus 10 includes an image reading section 11, an image forming section 12, a display section 41, an operation section 42, an internal temperature detecting section 43, an external temperature detecting section 49, a storage section 44, and a cooling fan. 48, a control unit 45, and the like. These components are capable of transmitting and receiving data or signals to and from each other via a bus.

The operation unit 42 is operated by a user. The operation unit 42 includes, for example, a start key for instructing the execution of functions possible by the image forming apparatus 1, a decision key (enter key) for confirming the user's (operator's) operation, and a key for inputting numerical values. Equipped with hard keys such as numerical input keys.

The operation unit 42 also includes a display unit 41 that displays operation guidance and the like to the user. The display unit 41 is a display device such as a liquid crystal display (LCD) or an organic light-emitting diode (OLED) display. The display section 41 includes a touch panel on its front surface, and the user can operate the image forming apparatus 1 by touching the images and icons displayed on the display section 41.

Here, the drive section 47 will be explained a little more using FIG. 5. FIG. 5 is a functional block diagram showing the main internal configuration of the drive section shown in FIG. 4. As shown in FIG. The drive unit 47 includes a first motor 47A, a first clutch 47B that can be switched between a transmission state in which the rotation of the first motor 47A is transmitted to the developing roller 27 and the spiral feeder 32 and a cutoff state in which it is interrupted, and a second motor 47E. and a second clutch 47F that can be switched between a transmission state in which the rotation of the second motor 47E is transmitted to the photoreceptor drum 4 and a cutoff state in which the rotation is interrupted. The first motor 47A and the second motor 47E are, for example, stepping motors. The first clutch 47B and the second clutch 47F are, for example, electromagnetic clutches. Note that the first motor 47A is an example of a motor in the claims, and the first clutch 47B is an example of a clutch in the claims.

For example, the developing roller 27 is rotationally driven in the direction of the arrow by the rotational force of the first motor 47A being transmitted to the developing roller 27 via the first clutch 47B in the transmission state. As shown in FIG. 3, the spiral feeder 32 is rotatably supported on an outer wall surface 31E of the developer storage section 31. As shown in FIG. Each spiral feeder 32 is rotationally driven in the direction of the arrow by transmitting the rotational force by the first motor 47A to the shaft portion 32A of each spiral feeder 32 via the first clutch 47B in the transmission state. The photosensitive drum 4 is rotationally driven in the direction of the arrow by the rotational force of the second motor 47E being transmitted to the photosensitive drum 4 via the second clutch 47F in the transmission state.

The internal temperature detection section 43 is a temperature sensor that detects the temperature around the developer, and is arranged at a predetermined position inside the image forming apparatus 10. Specifically, as shown in FIG. 3, the in-machine temperature detection section 43 is connected to a drive input section (for example, a drive input section of the first motor 47A) that drives the developing roller 27 and the spiral feeder 32 on the outer wall surface 31E of the developer storage section 31. It is arranged around the input gear G1) whose rotation is transmitted via the first clutch 47B, and the temperature of the outer wall surface 31E of the developer storage section 31 of the developing device 22 is adjusted to the internal temperature Ti of the image forming apparatus 10. Detected as. In addition, since the input gear G1 is configured such that the rotational force of the first motor 47A is transmitted via the first clutch 47B, heat from the first motor 47A and the first clutch 47B is transmitted. This is the part of the developer storage section 31 that has the highest temperature. This in-machine temperature Ti affects the temperature of the developer stored in the developer storage section 31 of the developing device 22, so the higher the in-machine temperature Ti becomes, the higher the temperature of the developer becomes.

Note that the cause of the temperature rise of the developer is, for example, when heat from the first motor 47A or the first clutch 47B is transmitted to the spiral feeder 32 and the developer via the gear mechanism including the input gear G1 and the shaft portion 32A of the spiral feeder 32. For example, it may be transmitted to the roller 27.

The external temperature detection unit 49 is a temperature sensor that detects the temperature outside the image forming apparatus 10, and is arranged at a predetermined position outside the image forming apparatus 10. For example, the external temperature detection section 49 is disposed at a predetermined location on the outer surface of the casing 10A of the image forming apparatus 10 (for example, a location around the suction port of the casing 10A), and 10 is detected as the external temperature To of the image forming apparatus 10.

The cooling fan 48 takes in air from outside the image forming apparatus 10 as cooling air from a suction port (not shown) formed in the casing 10A of the image forming apparatus 10, and uses the taken in cooling air to pass through the developing roller shown in FIG. In order to cool the sleeve of the developing roller 27 and the photoreceptor drum 24 by flowing around the space SP between the sleeve of the developing roller 27 and the photoreceptor drum 24 and along the longitudinal direction of the sleeve of the developing roller 27 and the photoreceptor drum 24. I'm a fan of. The cooling air is exhausted from an exhaust port (not shown) formed in the casing 10A of the image forming apparatus 10. The cooling air can be so small that the developer carried on the sleeve surface of the developing roller 27 and the surface of the photoreceptor drum 24 is not blown away. For example, the cooling fan 48 generates the above-mentioned breeze by rotating at a predetermined first rotation speed. Furthermore, by rotating at a predetermined second rotation speed that is higher than the first rotation speed, the cooling fan 48 can supply wind stronger than the above-mentioned breeze, thereby increasing the cooling effect.

The storage unit 44 is a storage device such as a RAM or a large-capacity HDD (Hard Disk Drive), and stores various data and programs. As shown in FIG. 6, the storage unit 44 stores in advance a reference table for specifying the development drive duty ratio of the development device 22, and a first threshold temperature Tf and a second threshold temperature Ts, which will be described later. FIG. 6 is a diagram showing a reference table for specifying the development drive duty ratio. The reference table is a data table showing the correspondence between the input data, which is the internal temperature Ti and the external temperature To, and the output data, which is the developing drive duty ratio, and is, for example, a look-up table. In the reference table, a plurality of internal temperatures Ti and a plurality of external temperatures To are stored, and a developing drive duty ratio uniquely determined by the internal temperature Ti and the external temperature To is determined based on the internal temperature Ti and the external temperature To. It is stored in association with each combination with the outside temperature To. For example, as shown in FIG. 6, when the internal temperature Ti is 39° C. and the external temperature To is 30° C. or more and less than 35° C., the developing drive duty ratio is specified as 50%. The development drive duty ratio is preset within a range that does not exceed the upper limit temperature of the developer. Note that the external temperature To in the reference table may be set in 1°C increments.

FIG. 7 is a diagram for explaining the developing drive duty ratio, which is represented by the ratio of printable time to print standby time. The development drive duty ratio is the proportion of the printable time t in a predetermined period T (for example, 60 seconds). For example, if the printable time t is 12 seconds, the development drive duty ratio is 20%.

The control unit 45 includes a processor, a RAM (Random Access Memory), a ROM (Read Only Memory), and the like. The processor is, for example, a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), or an MPU (Micro Processing Unit). This control unit 45 functions as a control section 46 when a control program stored in the ROM or storage section 44 is executed by the processor.

Control unit 45 manages overall control of image forming apparatus 10 . The control unit 45 is also connected to the image reading section 11, the image forming section 12, the display section 41, the operation section 42, the inside temperature detection section 43, the outside temperature detection section 49, the storage section 44, the cooling fan 48, etc. It controls these components and sends and receives signals and data to and from each component.

The control unit 46 serves as a processing unit that executes various processes, and also has a function of controlling the display unit 41.

Further, the control unit 46 controls the drive unit 47 in the image forming unit 12 to individually rotationally drive the developing roller 27, each spiral feeder 32, the photoreceptor drum 4, and the like.

Furthermore, the control unit 46 controls the cooling fan 48 to cause cooling air to flow along the sleeve of the developing roller 27 and the photosensitive drum 4 in the longitudinal direction.

The control unit 46 sets the first cooling mode or the second cooling mode as the cooling mode for cooling the developing device 22.

Specifically, when the control unit 46 receives a print job (print request), (i) the internal temperature Ti detected by the internal temperature detection unit 43 is set to a predetermined first threshold temperature Tf (for example, Tf =39° C.) (Ti<Tf), the first cooling mode is set in which continuous printing is possible, cooling control is performed, and printing related to the print job is started in continuous printing.

Further, when the control unit 46 receives a print job (print request), (ii) if the internal temperature Ti detected by the internal temperature detection unit 43 is equal to or higher than the first threshold temperature Tf (Ti≧Tf), Using the reference table, a second cooling mode is entered in which intermittent printing is performed at a development drive duty ratio determined by the machine internal temperature Ti detected by the machine internal temperature detection section 43 and the machine external temperature To detected by the machine external temperature detection section 49. Set. For example, as shown in FIG. 6, when the cabin temperature Ti detected by the cabin temperature detection unit 43 is 39°C, the control unit 46 determines that the cabin temperature Ti is equal to or higher than the first threshold temperature Tf, and determines that the cabin temperature Ti is equal to or higher than the first threshold temperature Tf. is 39° C., and the external temperature To is 32° C., the reference table is used to specify that the developing drive duty ratio is 50%.

Based on the setting of the second cooling mode, the control unit 46 displays in advance a display (for example, display M1 shown in FIG. 10, which will be described later) indicating that printing related to the print job will be executed by intermittent printing. is displayed on the display section 41.

Further, the control unit 46 sets the maximum number of printable sheets when the predetermined cycle T is all the printable time t as Pmax, the printable number of printable sheets printed in the printable time t as n, and prints the print request (print job ), the number of printable sheets n is calculated using the formula (1) of "n=Pmax×(t/T)". Next, the control unit 46 uses the formula (2) of "tp=(NR/n)×T" to calculate the printing time tp required when printing related to the print job is performed by intermittent printing, This calculated printing time tp (for example, a display of "Printing time is 90 seconds" in display M2 shown in FIG. 10, which will be described later) is displayed on the display unit 41 in advance.

Here, calculation of the printing time tp by the control unit 46 will be explained. FIG. 8(A) is a diagram illustrating an example of the printing time when a request for printing 72 sheets is received in the second cooling mode. In FIG. 8A, the control unit 46 calculates the printable time t = T x 0.8 (= development drive duty ratio is 80%) = 60 seconds x 0.8 = 48 seconds, and print standby time (T - t) = 60 seconds - 48 seconds = 12 seconds, and using the formula (1) of "n = Pmax x (t/T)", the number of printable sheets to be printed in the printable time t = 60 sheets/minute x (48 seconds/60 seconds) seconds) = 48 sheets. Next, the control unit 46 uses the formula (2) of "tp=(NR/n)×T" to calculate the printing time tp=(72 sheets) when printing related to the print job is performed by intermittent printing. /48 sheets) x 60 seconds = 90 seconds, and display "Printing time tp is 90 seconds" on the display section 41 in advance.

FIG. 8B is a diagram illustrating an example of the printing time when a request for printing 36 sheets is received in the second cooling mode. In FIG. 8B, the control unit 4 calculates the printable time t = T x 0.8 (= development drive duty ratio is 80%) = 60 seconds x 0.8 = 48 seconds, and print standby time (T - t) = 60 seconds - 48 seconds = 12 seconds, and using the formula (1) of "n = Pmax x (t/T)", the number of printable sheets to be printed in the printable time t = 60 sheets/minute x (48 seconds/60 seconds) seconds) = 48 sheets. Next, the control unit 46 uses the formula (2) of "tp=(NR/n)×T" to calculate the printing time tp=(36 sheets) when printing related to the print job is performed by intermittent printing. /48 sheets) x 60 seconds = 45 seconds, and the display section 41 displays in advance a message that says "Printing time tp is 45 seconds."

When the control unit 46 receives a print start instruction via the operation unit 42, the control unit 46 performs cooling control in the second cooling mode and starts printing related to the print job in intermittent printing. Specifically, in the second cooling mode, the control unit 46 responds to a print request by setting a printable time t and a print standby time that are set within a range that does not exceed the developer upper limit temperature every predetermined period T. Intermittent printing is performed with a development drive duty ratio set to (Tt).

On the other hand, upon receiving a cancellation instruction via the operation unit 42, the control unit 46 cancels printing related to the print job.

Further, the control unit 46 drives the developing device 22 during the printable time t, and does not drive the developing device 22 during the printing standby time (Tt). Specifically, the control unit 46 sets the first clutch 47B in the transmission state to drive the developing roller 27 and each spiral feeder 32 during the printable time t, and also sets the second clutch 47F in the transmission state to drive the photoreceptor drum. During the printing standby time (Tt), the first clutch 47B and the second clutch 47F are disconnected, and the developing roller 27, each spiral feeder 32, and the photosensitive drum 4 are not driven.

When set to the second cooling mode, the control unit 46 sets the in-machine temperature Ti detected by the in-machine temperature detection unit 43 to a predetermined second threshold temperature Ts (for example, Ts) that is lower than the first threshold temperature Tf. =38.5°C), the first cooling mode is returned to perform cooling control.

Next, cooling control of the developing device 22 in the image forming apparatus 10 will be explained with reference to the flowchart shown in FIG. FIG. 9 is a flowchart showing cooling control of the developing device in the image forming apparatus.

First, the control unit 46 acquires the temperature of the outer wall surface 31E of the developer storage section 31 of the developing device 22 detected by the internal temperature detection unit 43 as the internal temperature Ti of the image forming apparatus 10, and this internal temperature Ti is set in advance. It is determined whether the temperature is equal to or higher than a set fan operation threshold temperature T1 (for example, 35° C.) (S101). When the control unit 46 determines that the internal temperature Ti is equal to or higher than the fan operation threshold temperature T1 (S101 "Yes"), the control unit 46 drives the cooling fan 48 (S102). For example, the control unit 46 rotates the cooling fan 48 at the predetermined first rotation speed. On the other hand, if the control unit 46 determines that the internal temperature Ti is less than the fan operation threshold temperature T1 (S101 "No"), the control unit 46 stops the cooling fan 48 (S103).

First, the control unit 46 determines whether there is a print job for forming an image on recording paper (in other words, a print job for recording a visible image on recording paper) (S104). Here, it is assumed that the image forming apparatus 10 receives a print job to copy the set document paper by the number of copies specified by the user. For this reason, the control unit 46 specifies the number of set manuscript papers by having the image reading unit 11 read the set manuscript papers, and then prints by multiplying the number of manuscript papers by the specified number of copies. Specify the requested number of sheets NR. If the control unit 46 determines that there is no print job (S104 "No"), it ends this process. When the control unit 46 determines that there is a print job (S104 “Yes”), the control unit 46 determines whether the internal temperature Ti detected by the internal temperature detection unit 43 is equal to or higher than a preset first threshold temperature Tf. (S105).

For example, if the control unit 46 determines that the internal temperature Ti is less than the first threshold temperature Tf (S105 "Yes"), the control unit 46 sets the first cooling mode (S106). The control unit 46 causes the image forming unit 12 to execute continuous printing for the print job (S107). In the present embodiment, in the first cooling mode and the second cooling mode, when the internal temperature Ti is equal to or higher than the fan operation threshold temperature T1, the cooling fan 48 rotates at the first rotation speed, so that during continuous printing, the cooling fan 48 rotates at the first rotation speed. The above-mentioned breeze is also caused to flow along the longitudinal direction of the sleeve of the developing roller 27 and the photosensitive drum 4, thereby cooling the sleeve of the developing roller 27 and the photosensitive drum 4.

The control unit 46 determines whether the print job is finished (S108). If the print job has not ended (S108 "No"), that is, if the continuous printing of the print job has not ended, the control unit 46 returns to the process of S105. On the other hand, if the control unit 46 determines that there is no print job, that is, that continuous printing has ended (S108 "Yes"), it ends this process.

By the way, in the process of S105 described above, when the control unit 46 determines that the internal temperature Ti is not less than the first threshold temperature Tf, in other words, it is equal to or higher than the first threshold temperature Tf (S105 "No"), the developer storage section It is assumed that the temperature of the developer No. 31 is high, and the second cooling mode is set (S109). Subsequently, the control unit 46 acquires the temperature detected by the external temperature detection unit 49 as the external temperature To of the image forming apparatus 10 (S110). Then, the control unit 46 uses the detected internal temperature Ti and external temperature To and the reference table shown in FIG. is specified (S111). For example, as shown in FIG. 6, when the internal temperature Ti is 39° C. and the external temperature To is 30° C. or more and less than 35° C., the control unit 46 specifies the developing drive duty ratio as 50%. .

The control unit 46 causes the display unit 41 to display in advance a message indicating that printing related to the print job will be executed by intermittent printing (S112). FIG. 10 is a diagram showing an example of the display screen of the display unit. As shown in FIG. 10, the control unit 46 causes the display unit 41 to display in advance a display M1 stating "The print job will be executed in intermittent printing."

The control unit 46 calculates the printing time tp by intermittent printing using the above equations (1) and (2), and causes the display unit 41 to display the calculated printing time tp in advance (S113). For example, as described above with reference to FIG. ) to calculate the printing time tp = 90 seconds when printing for a print job is performed using intermittent printing, and as shown in Figure 10, "The printing time using intermittent printing is 90 seconds." The display M2 is displayed on the display unit 41 in advance. Furthermore, in the process of S104, the control unit 46 specifies the requested number of print sheets NR by multiplying the number of set manuscript sheets by the number of copies, and displays "Requested number of print sheets: 72" in the display M2 of FIG. ” is displayed on the display section 41. Further, the control unit 46 causes the display unit 41 to display a print start key K11 and a cancel key K12 along with the display M1 and the display M2.

When the control unit 46 receives a cancellation instruction via the operation unit 42, for example, an instruction from the user to press the cancel key K12 shown in FIG. Terminate it.

The control unit 46 does not accept a cancel instruction via the operation unit 42 (S114 “No”), but receives a print start instruction via the operation unit 42, for example, an instruction for the user to press the print start key K11 shown in FIG. (S115 "Yes"), as shown in FIG. 7, it is determined whether or not the present time is the printable time (S116). The developing device 22 or the like is caused to perform intermittent printing at a developing drive duty ratio (here, 50%) (S117). Note that if the control unit 46 determines that it is not the printable time (S116 "No"), the process returns to S116.

The control unit 46 determines whether the print job is finished (S118). If the print job has not ended (S118 "No"), that is, if intermittent printing has not ended for the print job, the control unit 46 determines whether the internal temperature Ti is less than the second threshold temperature Ts. (S119). When the control unit 46 determines that the internal temperature Ti is less than the second threshold temperature Ts (S119 "Yes"), the process proceeds to S106. On the other hand, if the control unit 46 determines that the internal temperature Ti is not less than the second threshold temperature Ts (S119 "No"), the process proceeds to S110. On the other hand, in the process of S118, if the control unit 46 determines that there is no print job, that is, that intermittent printing has ended (S118 "Yes"), this process ends.

As described above, according to the image forming apparatus 10 of the first embodiment, the power input section (for example, The temperature of the surrounding area of the input gear G1) is higher than other areas, and the temperature of this area is detected by the in-machine temperature detection section 43 as the in-machine temperature Ti, so the temperature of the part where the developer is exposed to the highest temperature Or the temperature in the vicinity thereof can be detected, and the discrepancy between the internal temperature Ti detected by the internal temperature detection section 43 and the temperature of the portion where the developer is exposed to the highest temperature can be reduced. In addition, when the inside temperature Ti detected by the inside temperature detection section 43 is equal to or higher than the first threshold temperature Tf, the control section 46 controls the inside temperature Ti detected by the inside temperature detection section 43 and the outside temperature detection section 49. Cooling control is performed by setting the second cooling mode to perform intermittent printing at the development drive duty ratio determined by the external temperature To, which maintains developer performance and guarantees image quality. The development temperature can be suppressed to within the upper limit temperature, and thermal deterioration of the developer can be appropriately reduced. Therefore, image defects and damage to the image forming apparatus due to developer deterioration can be prevented. Further, since printing can be permitted up to near the upper limit temperature of the developer even in a high-temperature environment, it is possible to avoid a decrease in printing productivity as much as possible and improve convenience. Furthermore, when receiving a print request (print job), the control unit 46 performs printing related to the print request if (i) the internal temperature detected by the internal temperature detection unit 43 is less than the first threshold temperature Tf; (ii) display in advance that when the internal temperature detected by the internal temperature detection unit 43 is equal to or higher than the first threshold temperature Tf, the printing related to the print request will be executed by intermittent printing. Since this is displayed on the display unit 41, the user can give an instruction to start printing via the operation unit 42 after confirming in advance that printing related to the print request will be executed in intermittent printing. When the control unit 46 receives a cancellation instruction via the operation unit 42, the control unit 46 cancels the printing related to the print request, so if the user does not want intermittent printing, the user can avoid the intermittent printing in advance, or By canceling the print request and changing to a print request with a reduced number of prints, short-term intermittent printing can be performed, and user convenience can be further improved.

In addition, in the second cooling mode, the control unit 46 responds to a print request with a printable time t and a print standby time (T- Suppose that intermittent printing is performed with a developing drive duty ratio set to t). Then, let Pmax be the maximum number of sheets to be printed when the predetermined period T is all the printable time t, let n be the number of printable sheets printed in the printable time t, and let NR be the requested number of prints related to the print request. Then, the control unit 46 calculates the number of printable sheets n using equation (1) of n=Pmax×(t/T), and calculates the number of printable sheets n using equation (2) of tp=(NR/n)×T. , calculates the printing time tp required when printing related to the print request is performed by intermittent printing, and causes the display unit 41 to display the calculated printing time tp in advance. Therefore, the user can grasp the printing time tp required when printing related to a print request is performed by intermittent printing, and can take actions such as whether to instruct the start of the print request or change the print request to new content. can be determined more accurately, and user convenience can be further improved.

Moreover, when the control unit 46 is set to the second cooling mode and the internal temperature Ti detected by the internal temperature detection unit 43 is less than the second threshold temperature Ts, which is lower than the first threshold temperature Tf, Since cooling control is performed by returning to the first cooling mode, unstable mode transitions can be reduced compared to a configuration in which the first cooling mode is returned only by the first threshold temperature Tf. The printing operation behavior when returning to the first cooling mode can be reduced.

In addition, in the second cooling mode, the control unit 46 responds to a print request with a printable time t and a print standby time (T- Since intermittent printing is performed with a development drive duty ratio set to t), the development temperature can be suppressed to within the upper limit temperature of the developer, and thermal deterioration of the developer can be appropriately reduced.

Further, since the control unit 46 drives the developing device 22 during the printable time t and does not drive the developing device 22 during the printing standby time (Tt), the developing device 22 is driven during the printing standby time (Tt). It is possible to prevent heat generation caused by Therefore, the cooling effect during printing standby time (Tt) can be improved.

Further, the control unit 46 sets the first clutch 47B in a transmission state to drive the developing device 22 and the spiral feeder 32 during the printable time t, and sets the first clutch 47B in a disengaged state during the print standby time (Tt). Since the developing device 22 and the spiral feeder 32 are not driven, it is possible to prevent heat generation due to the driving of the developing roller and the spiral feeder 32 during the printing standby time (Tt). Therefore, the cooling effect during printing standby time (Tt) can be improved.

Furthermore, during the print standby time (Tt) in the second cooling mode, the control unit 46 operates the cooling fan 48 at a predetermined second rotation speed that is higher than the first rotation speed in the first cooling mode. Since this operation is performed, the cooling effect during printing standby time (Tt) can be further improved.

Furthermore, the storage unit 44 stores in advance a reference table showing the correspondence between the input data, which is the internal temperature Ti and the external temperature To, and the output data, which is the developing drive duty ratio. The control unit 46 uses the internal temperature Ti detected by the internal temperature detection unit 43, the external temperature To detected by the external temperature detection unit 49, and the reference table stored in the storage unit 44 to determine the developing drive duty ratio. Identify. Thereby, the developing drive duty ratio can be suitably specified.

In the above embodiment, as shown in FIG. is arranged around the input gear G1) whose rotation is transmitted via the first clutch 47B, and the temperature of the outer wall surface 31E of the developer storage section 31 is detected as the internal temperature Ti of the image forming apparatus 10. However, it is not limited to this. The in-machine temperature detection section 43 is connected to a drive input section (for example, the rotation of the first motor 47A) that drives the developing roller 27 and the spiral feeder 32 at a location indicated by a broken line in FIG. may be arranged around the input gear G1) that is transmitted via the first clutch 47B, and the temperature of the inner wall surface 31F of the developer storage section 31 may be detected as the internal temperature Ti. Further, the in-machine temperature detection section 43 may be disposed at a location where the developing roller 27 is supported on the inner wall surface 31F of the developer storage section 31, and may detect the surface temperature of the sleeve of the developing roller 27 as the in-machine temperature Ti. In these cases, the temperature of the area around the support area of the spiral feeder 32 or the area around the support area of the developing roller 27 on the inner wall surface 31F of the developer storage section 31 is higher than other areas, and Since the internal temperature detection section 43 detects the temperature, it is possible to detect the temperature of the part where the developer is exposed to the highest temperature or the temperature in the vicinity thereof, and the internal temperature detected by the internal temperature detection section 43 and the temperature of the developer at the highest temperature can be detected. It is possible to reduce the deviation from the temperature of the part exposed to the temperature.

Next, an image forming apparatus 10 according to a second embodiment will be described using FIG. 11. FIG. 11 is a functional block diagram showing the main internal configuration of an image forming apparatus according to the second embodiment.

The image forming apparatus 10 according to the second embodiment further includes a network interface section 91, and the control section 46 executes intermittent printing in response to a print request (print job) from an external computer 200. Since this embodiment differs from the first embodiment described above in that the computer 200 is caused to transmit display data indicating the above, the network interface section 91 and the control section 46 will be explained. Computer 200 is, for example, a personal computer, a mobile information terminal, or the like. Note that the computer 200 is an example of an information processing device within the scope of the claims.

The network interface unit 91 is composed of a communication module such as a LAN board, and transmits and receives various data to and from the computer 200 in the local area via a LAN or the like connected to the network interface unit 91. The network interface unit 91 also receives a print job from the computer 200, sends display data (described later) (that is, display data indicating that intermittent printing will be executed) to the computer 200, and receives a print job from the computer 200. It is possible to receive an instruction or a cancellation instruction. A plurality of computers 200 can be connected to the image forming apparatus 1. Note that the network interface section 91 is an example of a communication section in the claims.

Cooling control in the second embodiment will be explained using FIG. 12. FIG. 12 is a flowchart showing cooling control of the developing device in the image forming apparatus of the second embodiment. Since S101 to S111 and S116 to S119 shown in FIG. 12 are the same as in the case of FIG. 9, S112A, S113A, S114A, and S115A, which are characteristic parts of the second embodiment, will be described in detail.

After the process of S111 shown in FIG. 12, the control unit 46 causes the computer 200 that has transmitted the print job to transmit display data indicating that printing related to the print job will be executed in intermittent printing to the network interface unit 91 ( S112A).

After the processing in S112A above, the control unit 46 calculates the printing time tp by intermittent printing using the above equations (1) and (2), and displays the display data indicating the calculated printing time tp in the print The computer 200 that sent the job is caused to send it to the network interface unit 91 (S113A). For example, as described above with reference to FIG. ) is used to calculate the printing time tp = 90 seconds when printing related to the print job is performed by intermittent printing, and print display data indicating that "printing time by intermittent printing is 90 seconds". The computer 200 that has sent the job is caused to send it to the network interface unit 91. In addition, in the process of S104, the control unit 46 specifies the requested number of print sheets NR by multiplying the number of set manuscript sheets by the number of copies, and confirms that "the requested number of print sheets is 72." The network interface unit 91 is caused to transmit the requested print number display data shown in FIG.

When the network interface unit 91 receives cancellation instruction information from the computer 200 that has transmitted the print job, for example, cancellation instruction information indicating that the user of the computer 200 has canceled printing (S114A "Yes"), the control section 46 Cancels printing related to the print job and ends this process.

The control unit 46 determines that the network interface unit 91 has not received the cancellation instruction information (S114A "No") and print start instruction information from the computer 200 that has sent the print job, for example, indicates that the user of the computer 200 has started printing. When the network interface section 91 receives the print start instruction information (S115A "Yes"), as shown in FIG. 7, it is determined whether the current time is a printable time (S116). The subsequent steps are the same as those in the first embodiment described above, so the explanation here will be omitted.

According to the image forming apparatus 10 of the second embodiment, when the control unit 46 receives a print request from the computer 200 via the network interface unit 91, (i) the internal temperature detected by the internal temperature detection unit is less than a predetermined first threshold temperature, set to a first cooling mode, perform cooling control in the first cooling mode, and start printing related to the print request in continuous printing; (ii) When the internal temperature detected by the internal temperature detection unit is equal to or higher than the first threshold temperature, display data indicating that the second cooling mode is set and printing related to the print request will be executed intermittently is sent to the computer 200 in advance. When the network interface unit 91 receives a print start instruction via the network interface unit 91, cooling control is performed in the second cooling mode and printing related to the print request is started in intermittent printing. A user who sends a print request from the computer 200 can be informed in advance whether continuous printing or intermittent printing is being performed, and the user can confirm in advance whether continuous printing or intermittent printing is being performed. Then, an instruction to start printing can be given to the image forming apparatus. When the control unit 46 receives a cancellation instruction via the network interface unit 91, it cancels printing related to the print request, so if the user who sent the print request from the external computer 200 does not desire intermittent printing, It is possible to avoid intermittent printing in advance, or cancel the print request and change it to a print request with a reduced number of prints, resulting in short-term intermittent printing, further improving user convenience. can be done.

In addition, in the second cooling mode, the control unit 46 responds to a print request with a printable time t and a print standby time (T- Suppose that intermittent printing is performed with a developing drive duty ratio set to t). Then, let Pmax be the maximum number of sheets to be printed when the predetermined period T is all the printable time t, let n be the number of printable sheets printed in the printable time t, and let NR be the requested number of prints related to the print request. Then, the control unit 46 calculates the number of printable sheets n using equation (1) of n=Pmax×(t/T), and calculates the number of printable sheets n using equation (2) of tp=(NR/n)×T. , calculates the printing time tp required when printing related to the print request is performed by intermittent printing, and causes the computer 200 to transmit printing time data indicating the calculated printing time tp to the network interface unit 91 in advance. Therefore, the user who sent the print request from the external computer 200 can grasp the printing time tp required when printing related to the print request is performed by intermittent printing, and can determine whether to instruct the start of the print request or not. It is possible to more accurately judge whether to change to new content, etc., and the user's convenience can be further improved.

<First modification example>
In each of the above embodiments, as shown in FIG. 7, the predetermined period T is divided into the first half and the second half. ), but is not limited to this aspect. FIG. 13 is a diagram for explaining the developing drive duty ratio of the first modification. In the first modification, as intermittent printing at the development drive duty ratio in the second cooling mode, a unit set of printing unit time Δt per sheet and printing standby unit time Δtr per sheet is repeated for the number of requested print sheets NR. It is also possible to perform intermittent printing.

In FIG. 13, the same conditions as in FIG. 8(B) are used, namely, the predetermined period T is 60 seconds, the maximum number of print sheets Pmax is 60 sheets/min, the development drive duty ratio is 80%, and the requested number of print sheets NR is In the case of 36 sheets, the control unit 46 calculates the printable time t = T x 0.8 (= development drive duty ratio is 80%) = 60 seconds x 0.8 = 48 seconds, and calculates the print standby time ( T - t) = 60 seconds - 48 seconds = 12 seconds, and using the formula (1) of "n = Pmax x (t / T)", the number of printable sheets to be printed in the printable time t = n = Calculate 60 sheets/minute x (48 seconds/60 seconds) = 48 sheets. Next, the control unit 46 uses the formula (2) of "tp=(NR/n)×T" to calculate the printing time tp=(36 sheets) when printing related to the print job is performed by intermittent printing. /48 sheets) x 60 seconds = 45 seconds, and the display section 41 displays in advance a message that says "Printing time tp is 45 seconds." Everything up to this point is the same as each of the embodiments described above.

The control unit 46 uses the following equation (3) to calculate the print unit time Δt per sheet, and uses the following equation (4) to calculate the printing standby unit time Δtr per sheet.
Δt=T/Pmax...(3)
Δtr=(T-t)/n...(4)

The control unit 46 calculates the printing unit time per sheet Δt=60 seconds/60 sheets=1 second using the equation (3) of “Δt=T/Pmax”, and calculates “Δtr=(T−t)”. /n'' is used to calculate the print standby unit time Δtr per sheet = (60 seconds - 48 seconds)/48 sheets = 0.25 seconds.

Then, the control unit 46 controls the printing unit time Δt (=1 second) per sheet and the print standby unit time Δtr (=0.25 Intermittent printing is performed in which the unit set with NR (seconds) is repeated by the number of requested print sheets NR (=36 sheets). The printing time in this case is (1 second + 0.25 seconds) x 36 seconds = 45 seconds, and the printing time tp required when printing related to the print job is performed by intermittent printing = (36 sheets / 48 sheets) The value is the same as x60 seconds = 45 seconds.

In this way, in the first modification, the control unit 46 calculates the printing unit time Δt per sheet using the formula (3) of Δt=T/Pmax, and calculates the printing unit time Δt of Δtr=(T−t)/n. Using equation (4), calculate the printing standby time Δtr per sheet, and calculate the printing unit time Δt per sheet and the printing per sheet as intermittent printing at the development drive duty ratio in the second cooling mode. Intermittent printing is performed in which the unit set with the standby unit time Δtr is repeated by the number of requested print sheets NR. As a result, after one sheet is printed in the printing unit time Δt per sheet, printing is put on standby in the print standby unit time Δtr per sheet and cooling is performed in the second cooling mode, so that the printing per sheet is Compared to a configuration in which the unit time Δt is continuous, it is possible to suppress the temperature increase of the developer and avoid a decrease in printing productivity as much as possible.

Next, an image forming apparatus 10 according to a second modification will be described.

In addition to the reference table shown in FIG. 6, the storage unit 44 of the image forming apparatus 10 according to the second modification determines whether or not to display a message indicating that intermittent printing will be performed, as shown in FIG. It further includes a determination table for determining.

FIG. 14 is a diagram showing a determination table in which the upper limit number of sheets for intermittent printing is set in advance for each correspondence relationship between the input data, which is the temperature inside the machine and the temperature outside the machine. The determination table is a data table in which the upper limit number of intermittent printing sheets is set in advance for each correspondence relationship between the input data of the internal temperature and the external temperature, and is, for example, a look-up table. For example, as shown in FIG. 14, when the internal temperature Ti is 39° C. and the external temperature To is 35° C. or more and less than 40° C., the upper limit number of sheets for intermittent printing is specified as 240 sheets.

After setting the second cooling mode, the control unit 46 uses the machine interior temperature Ti detected by the machine interior temperature detection unit 43, the machine exterior temperature To detected by the machine exterior temperature detection unit 49, and the determination table shown in FIG. (iiA) If the requested number of print sheets NR for a print job is less than or equal to the upper limit for intermittent printing, display in advance that printing for the print job will be performed using intermittent printing. The printing related to the print job is executed during the first half of the printing time tp, which is the time "tp x (t/T)", without displaying it on the display unit 41, and Start with intermittent printing in which printing is on standby in the period after the period, and (iiB) If the requested number of print sheets NR for the print job exceeds the upper limit number of sheets for intermittent printing, printing for the print job is executed in intermittent printing. Display on the display unit 41 in advance a message indicating that the printing unit time Δt per sheet is calculated using the following formula (3), and the print standby time per sheet is calculated using the following formula (4). The time Δtr is calculated, Δt=T/Pmax...(3), Δtr=(T-t)/n...(4), and upon receiving a print start instruction via the operation unit 42, printing related to the print job is started. , as intermittent printing at the development drive duty ratio in the second cooling mode, the unit set of printing unit time Δt per sheet and printing standby unit time Δtr per sheet is repeated for the number of requested print sheets NR. Let it start.

The cooling control of the second modification will be explained using FIG. 15. FIG. 15 is a flowchart showing cooling control of the developing device in the image forming apparatus of the second modification. Since S101 to S119 shown in FIG. 15 are the same as in the case of FIG. 9, S111A, which is a characteristic part of the second modification, will be described in detail. FIGS. 16A and 16B are diagrams for explaining intermittent printing in the second modification, respectively.

After the processing in S111 shown in FIG. 15, the control unit 46 determines whether to display a message indicating that printing related to the print job will be executed in intermittent printing (S111A). For example, as shown in FIG. 16A, when the machine internal temperature Ti is 40°C and the external temperature To is 39°C, the control unit 46 specifies that the upper limit number of intermittent printing sheets is 80 sheets. do. Subsequently, the control unit 46 (iiA) if the requested number of print sheets NR related to the print job is less than or equal to the upper limit number of intermittent printing sheets (for example, 72 sheets shown in FIG. 16(A)), If it is determined that the display indicating that printing will be performed by intermittent printing is not displayed in advance on the display unit 41 (S111A "No"), the process proceeds to S116, and it is determined that the printable time has come (S116 "Yes"). Printing related to the print job is executed during the first half of the printing time tp, at a time of "tp x (t/T)" (72 seconds of the first half period shown in FIG. 16(A)). , and starts intermittent printing (intermittent printing shown in FIG. 16A) in which printing is on standby in the period after the first half period (S117).

On the other hand, (iiB) if the requested print number NR for the print job exceeds the intermittent printing upper limit number (80 sheets in this case) (for example, 82 sheets shown in FIG. 16(B)), It is determined that a display indicating that printing related to the print job will be executed by intermittent printing is to be displayed on the display unit 41 in advance (S111A “Yes”), and a display indicating that printing will be executed by intermittent printing is displayed on the display unit 41 in advance. Display (S112), the print unit time Δt per sheet is calculated using the following equation (3), and the printing standby unit time Δtr per sheet is calculated using the following equation (4).
Δt=T/Pmax...(3)
Δtr=(T-t)/n...(4)

Subsequently, when the control unit 46 receives an instruction to start printing via the operation unit 42 (S115 "Yes"), the process proceeds to S116, and if it is determined that it is the printable time (S116 "Yes"), the control unit 46 responds to the print request. Such printing is assumed to be intermittent printing at the development drive duty ratio in the second cooling mode, and the unit set of printing unit time Δt per sheet and printing standby unit time Δtr per sheet is repeated for the requested number of print sheets NR. Intermittent printing (intermittent printing shown in FIG. 16(B)) is started (S117). In other words, as shown in FIG. 16(B), if it is the same as (iiA) above, the user will have to wait in the standby state for 720 seconds = 8 minutes, so the printing unit time Δt per sheet and the printing unit time per sheet Intermittent printing is performed in which the unit set with the printing standby unit time Δtr is repeated by the number of requested print sheets NR. Therefore, the user can understand that intermittent printing is being executed, and can prevent the user from having to wait in a standby state for eight minutes.

As described above, according to the image forming apparatus 10 of the second modification, when the requested number of print sheets NR for a print job is less than or equal to the upper limit number of sheets for intermittent printing, the printing for the print job is executed by intermittent printing. Printing related to the print job can be started with intermittent printing shown in FIG. 16(A) without displaying the display on the display unit 41 in advance. That is, even in the second cooling mode, if the number of sheets NR requested by the user to print is equal to or less than the upper limit number of sheets for intermittent printing, intermittent printing can be performed without making the user wait for a long time. On the other hand, if the requested number of print sheets NR exceeds the upper limit number of sheets for intermittent printing, the display section 41 displays in advance a message to the effect that the printing related to the print job will be executed by intermittent printing, and the user is prompted to wait for intermittent printing. The user can be informed in advance that this will occur, and based on this, the user can select whether or not to perform intermittent printing as shown in FIG. Changes can be made.

Furthermore, the process of S111A in the flowchart of the second modification example shown in FIG. 15 may be added between S111 and S112A in the flowchart of the second embodiment shown in FIG. In this case, in the image forming apparatus 10 of the second embodiment, display determination using the determination table of FIG. 14 can be realized.

That is, after setting the second cooling mode, the control unit 46 uses the machine interior temperature Ti detected by the machine interior temperature detection unit 43, the machine exterior temperature To detected by the machine exterior temperature detection unit 49, and the determination table shown in FIG. is used to identify the upper limit number of sheets for intermittent printing, and (iiA) if the requested number of sheets NR for the print job is less than or equal to the upper limit for intermittent printing, an indication that printing for the print job will be executed by intermittent printing. without causing the computer 200 to send data to the network interface unit 91 in advance, printing related to the print job is started in intermittent printing, and (iiB) the number of requested print sheets NR related to the print job exceeds the upper limit number of sheets for intermittent printing. In this case, if the computer 200 sends display data to the network interface unit 91 in advance indicating that printing related to the print job will be executed by intermittent printing, and receives an instruction to start printing via the operation unit 42, the print job will be executed intermittently. A configuration is realized in which printing related to a print job is started intermittently.

In each embodiment and each modification, the control unit 46 controls the printing time tp by intermittent printing, including the printing standby time in the last cycle T, as shown in FIGS. 8(A) and 8(B). However, the time obtained by subtracting the printing standby time in the last cycle T from the printing time tp calculated using the above equation (2) may be displayed as the printing time by intermittent printing.

Further, in each embodiment and each modification example, the reference table shown in FIG. 6 is used, but a relational expression for calculating the development drive duty ratio may be used. For example, the storage unit 44 stores in advance a relational expression for calculating the developing drive duty ratio using the input data of the internal temperature Ti and the external temperature To. The control unit 46 calculates the developing drive duty ratio using the internal temperature Ti detected by the internal temperature detection unit 43, the external temperature To detected by the external temperature detection unit 49, and the relational expression. Also in this case, the developing drive duty ratio can be suitably calculated.

Further, in the above embodiment and each modification example, the drive section 47 shown in FIG. 5 includes the first clutch 47B and the second clutch 47F, but it may be configured without a clutch. In this case, the control unit 46 may stop the rotation of the first motor 47A and the second motor 47E during the print standby time (Tt).

Further, although a one-component developer such as one-component magnetic toner is illustrated as the developer stored in the developer storage section 31, a two-component developer made by mixing toner and carrier is used. The present invention can also be applied to.

Further, in the above embodiments, a multifunction device is exemplified as an embodiment of the image forming apparatus of the present invention, but this is only an example, and the image forming apparatus may be a copy machine, a printer, a facsimile machine, or the like.

Further, the configuration of the above embodiment described using FIGS. 1 to 16 is only an example of the present invention, and is not intended to limit the present invention to this configuration.

4 Photosensitive drum (image carrier)
10 Image forming device 22 Developing device 27 Developing roller 31 Developer storage section 32 Spiral feeder (stirring member)
41 Display section 42 Operation section 43 Inside temperature detection section 44 Storage section 46 Control section 48 Cooling fan 49 Outside temperature detection section

Claims (9)

An image forming apparatus including a developing device,
The developing device includes:
a developing roller that applies a developer to the electrostatic latent image formed on the image carrier to develop the electrostatic latent image into a visible image;
a developer accommodating section that includes a stirring member that stirs the developer while conveying the developer along the developing roller, and supplies the developer to the developing roller;
an in-machine temperature detection section that is disposed on an outer wall surface of the developer accommodating section around a drive input section that drives the developing roller and the stirring member, and that detects the temperature of the outer wall surface of the developer accommodating section as an in-machine temperature; , comprising;
The image forming apparatus includes:
A display section;
an operation section operated by a user;
an external temperature detection section that detects the temperature outside the image forming apparatus;
When receiving a print request, (i) if the internal temperature detected by the internal temperature detection section is less than a predetermined first threshold temperature, set to a first cooling mode in which continuous printing is possible; performing cooling control in a first cooling mode and starting printing related to the printing request in the continuous printing; The second cooling mode is set to perform intermittent printing at the development drive duty ratio determined by the machine internal temperature detected by the machine internal temperature detection unit and the machine external temperature detected by the machine external temperature detection unit, and printing related to the print request is performed. displays on the display section in advance a message indicating that the intermittent printing will be performed, and upon receiving an instruction to start printing via the operation section, performs cooling control in the second cooling mode and performs cooling control related to the printing request. a control unit that starts printing with the intermittent printing and, upon receiving a cancellation instruction via the operation unit, cancels the printing related to the print request ;
further comprising a communication unit that performs data communication with an external information processing device,
When the control unit receives a print request from the information processing device as the print request via the communication unit, (i) the internal temperature detected by the internal temperature detection unit is a predetermined first threshold temperature; If the temperature is less than 1, the temperature is set to the first cooling mode, cooling control is performed in the first cooling mode, and printing related to the print request is started in the continuous printing; (ii) the internal temperature detection unit detects the temperature. If the internal temperature of the machine is equal to or higher than the first threshold temperature, the second cooling mode is set, and display data indicating that printing related to the print request will be executed in the intermittent printing is sent to the information processing device in advance. When the printing start instruction is received through the communication unit, cooling control is performed in the second cooling mode, and printing related to the print request is started in the intermittent printing, and the communication An image forming apparatus that cancels printing related to a print request when receiving a cancellation instruction via the print department . An image forming apparatus including a developing device,
The developing device includes:
a developing roller that applies a developer to the electrostatic latent image formed on the image carrier to develop the electrostatic latent image into a visible image;
a developer accommodating section that includes a stirring member that stirs the developer while conveying the developer along the developing roller, and supplies the developer to the developing roller;
an in-machine temperature detection section that is disposed on an outer wall surface of the developer accommodating section around a drive input section that drives the developing roller and the stirring member, and that detects the temperature of the outer wall surface of the developer accommodating section as an in-machine temperature; , comprising;
The image forming apparatus includes:
A display section;
an operation section operated by a user;
an external temperature detection section that detects the temperature outside the image forming apparatus;
When receiving a print request, (i) if the internal temperature detected by the internal temperature detection section is less than a predetermined first threshold temperature, set to a first cooling mode in which continuous printing is possible; performing cooling control in a first cooling mode and starting printing related to the printing request in the continuous printing; The second cooling mode is set to perform intermittent printing at the development drive duty ratio determined by the machine internal temperature detected by the machine internal temperature detection unit and the machine external temperature detected by the machine external temperature detection unit, and printing related to the print request is performed. displays on the display section in advance a message indicating that the intermittent printing will be performed, and upon receiving an instruction to start printing via the operation section, performs cooling control in the second cooling mode and performs cooling control related to the printing request. a control unit that starts printing with the intermittent printing and, upon receiving a cancellation instruction via the operation unit, cancels the printing related to the print request;
In the second cooling mode, the control unit responds to the print request by setting a printable time t and a print standby time (T- Suppose that intermittent printing is performed with the development drive duty ratio set to t),
The maximum number of printable sheets when the predetermined period T is all the printable time t is Pmax, the printable number of sheets printed in the printable time t is n, and the print request number of sheets related to the print request is If it is NR,
Further, the control unit calculates the number of printable sheets n using the following equation (1), and calculates the number of printable sheets n using the following equation (2) when printing according to the print request is performed by the intermittent printing. An image forming apparatus that calculates the printing time tp and displays the calculated printing time tp on the display section in advance.
n=Pmax×(t/T)...(1)
tp=(NR/n)×T…(2) In the second cooling mode, the control unit responds to the print request by setting a printable time t and a print standby time (T- Suppose that intermittent printing is performed with the development drive duty ratio set to t),
The maximum number of printable sheets when the predetermined period T is all the printable time t is Pmax, the printable number of sheets printed in the printable time t is n, and the print request number of sheets related to the print request is If it is NR,
Further, the control unit calculates the number of printable sheets n using the following equation (1), and calculates the number of printable sheets n using the following equation (2) when printing according to the print request is performed by the intermittent printing. The image forming apparatus according to claim 1 , wherein the printing time tp is calculated, and printing time data indicating the calculated printing time tp is sent to the communication unit of the information processing apparatus in advance.
n=Pmax×(t/T)...(1)
tp=(NR/n)×T…(2) The control unit calculates a printing unit time Δt per sheet using the following equation (3), calculates a printing standby unit time Δtr per sheet using the following equation (4),
Δt=T/Pmax...(3)
Δtr=(T-t)/n...(4)
As intermittent printing at the development drive duty ratio in the second cooling mode, a unit set of a print unit time Δt per sheet and a print standby unit time Δtr per sheet is repeated for the requested print number NR. The image forming apparatus according to claim 2 or 3 , wherein the image forming apparatus performs printing. The image according to any one of claims 2 to 4 , wherein the control unit drives the developing device during the printable time t, and does not drive the developing device during the print standby time (Tt). Forming device. An image forming apparatus including a developing device,
The developing device includes:
a developing roller that applies a developer to the electrostatic latent image formed on the image carrier to develop the electrostatic latent image into a visible image;
a developer accommodating section that includes a stirring member that stirs the developer while conveying the developer along the developing roller, and supplies the developer to the developing roller;
an in-machine temperature detection section that is disposed on an outer wall surface of the developer accommodating section around a drive input section that drives the developing roller and the stirring member, and that detects the temperature of the outer wall surface of the developer accommodating section as an in-machine temperature; , comprising;
The image forming apparatus includes:
A display section;
an operation section operated by a user;
an external temperature detection section that detects the temperature outside the image forming apparatus;
When receiving a print request, (i) if the internal temperature detected by the internal temperature detection section is less than a predetermined first threshold temperature, set to a first cooling mode in which continuous printing is possible; performing cooling control in a first cooling mode and starting printing related to the printing request in the continuous printing; The second cooling mode is set to perform intermittent printing at the development drive duty ratio determined by the machine internal temperature detected by the machine internal temperature detection unit and the machine external temperature detected by the machine external temperature detection unit, and printing related to the print request is performed. displays on the display section in advance a message indicating that the intermittent printing will be performed, and upon receiving an instruction to start printing via the operation section, performs cooling control in the second cooling mode and performs cooling control related to the printing request. a control unit that starts printing with the intermittent printing and, upon receiving a cancellation instruction via the operation unit, cancels the printing related to the print request;
further comprising a storage unit that stores in advance a reference table showing the correspondence between the input data, which is the inside temperature and the outside temperature, and the developing drive duty ratio, which is the output data;
The control unit specifies the developing drive duty ratio using the internal temperature detected by the internal temperature detection unit, the external temperature detected by the external temperature detection unit, and the reference table. . further comprising a storage unit that stores in advance a reference table showing the correspondence between the input data, which is the inside temperature and the outside temperature, and the developing drive duty ratio, which is the output data;
1 . The control unit specifies the developing drive duty ratio using the internal temperature detected by the internal temperature detection unit, the external temperature detected by the external temperature detection unit, and the reference table. The image forming apparatus according to claim 5 . further comprising a storage unit that stores in advance a determination table in which the upper limit number of intermittent printing sheets is set in advance for each correspondence relationship with the input data of the internal temperature and the external temperature,
After the second cooling mode is set, the control section uses the machine interior temperature detected by the machine interior temperature detection section, the machine exterior temperature detected by the machine exterior temperature detection section, and the determination table to control the intermittent cooling mode. Specify the maximum number of prints,
(iiA) If the requested number of print sheets NR related to the print request is less than or equal to the upper limit number of sheets for intermittent printing, display in advance on the display unit a display that the printing related to the print request will be executed by the intermittent printing. The printing related to the print request is executed in the first half of the printing time tp at a time of "tp x (t/T)" without causing any interruption, and in the period after the first half period. Start with intermittent printing that waits for printing,
(iiB) If the requested number of print sheets NR related to the print request exceeds the upper limit number of sheets for intermittent printing, display in advance on the display section a message that the printing related to the print request will be executed by the intermittent printing. , Calculate the printing unit time Δt per sheet using the following formula (3), Calculate the printing standby unit time Δtr per sheet using the following formula (4),
Δt=T/Pmax...(3)
Δtr=(T-t)/n...(4)
When a print start instruction is received via the operation unit, printing related to the print request is performed as intermittent printing at the development drive duty ratio in the second cooling mode, and the printing unit time Δt per sheet and the printing unit time per sheet are determined. 3. The image forming apparatus according to claim 2 , wherein the image forming apparatus starts intermittent printing in which the unit set with the printing standby unit time Δtr is repeated by the number of requested print sheets NR. further comprising a storage unit that stores in advance a determination table in which the upper limit number of intermittent printing sheets is set in advance for each correspondence relationship with the input data of the internal temperature and the external temperature,
After the second cooling mode is set, the control section uses the machine interior temperature detected by the machine interior temperature detection section, the machine exterior temperature detected by the machine exterior temperature detection section, and the determination table to control the intermittent cooling mode. Specify the maximum number of prints,
(iiA) If the requested number of print sheets NR related to the print request is equal to or less than the upper limit number of sheets for intermittent printing, display data indicating that printing related to the print request will be executed by the intermittent printing is sent to the information processing device in advance. The printing according to the print request is executed during the first half of the print time tp at a time of "tp x (t/T)" without causing the communication unit to send the print request, and , start with intermittent printing that waits for printing in the period after the first half period,
(iiB) If the requested number of print sheets NR related to the print request exceeds the upper limit number of sheets for intermittent printing, display data indicating that printing related to the print request will be executed by the intermittent printing is sent to the information processing device in advance. The communication unit transmits the information to the communication unit, calculates the print unit time Δt per sheet using the following formula (3), and calculates the print standby unit time Δtr per sheet using the following formula (4). death,
Δt=T/Pmax...(3)
Δtr=(T-t)/n...(4)
When a print start instruction is received via the communication unit, printing related to the print request is performed as intermittent printing at the development drive duty ratio in the second cooling mode, and the printing unit time Δt per sheet and the printing unit time per sheet are determined. 4. The image forming apparatus according to claim 3 , wherein the image forming apparatus starts intermittent printing in which the unit set with the printing standby unit time Δtr is repeated by the number of requested print sheets NR.